In recent years, a large number of surveillance cameras have been installed in various locations such as offices, shopping centers, and shopping streets. Also, there has been a move to comprehend the attributes and actions of people from these surveillance images for application in marketing.
Within this move, International Publication Pamphlet No. WO 2011/046128 discloses a technology that detects a person region from an input image of a surveillance camera, and determines a movement of a person in the person region. In this technology, the separability of the clothing of the person is determined to generate clothing portion separation information, and, in addition, clothing features indicating visual features of the clothing of the person in the person region are extracted taking into account the orientation of the person and the clothing portion separation information. The orientation of the person is determined based on the orientation of the face of the person, the movement of the person, and the symmetry of the clothing. The person is then retrieved based on a collation result between clothing query text indicating the type and color of the clothing of the person and the extracted clothing features of the person.
Japanese Laid-open Patent Publication No. 2007-258923 discloses an example in which an edge portion in a first image from among a plurality of images photographed using a plurality of photographing conditions is detected.
Japanese Laid-open Patent Publication No. 2003-263641 discloses a movement analysis device that has cameras, image processing devices, and a data integration analysis device. The cameras are a plurality of imaging devices that photograph images of a plurality of ranges within a specific region. The image processing devices process the images and extract feature values of a moving object that moves within the images and locus data that indicates the locus of the moving object within the respective ranges analyzed from the images. The data integration analysis device collates data of the feature values to verify the moving object photographed in the respective ranges, and integrates the locus data of the same moving object to create movement data indicating the state of the movement of the moving object within the region.
Furthermore, Japanese Laid-open Patent Publication No. 2011-18238 discloses a technology that divides an image acquired from an image or the like photographed by a camera into blocks of a prescribed size, and, based on a color histogram, extracts feature values of the blocks, and retrieves a target person.
Japanese Laid-open Patent Publication No. 2002-157599 discloses a technique for successively detecting one or more moving objects from a plurality of image signals successively input from a camera, through the use of a background difference method, a dynamic binary method, and template matching, and determining whether or not the moving objects belong to specific surveillance-target moving objects.
Furthermore, Japanese Laid-open Patent Publication No. 2014-92886 discloses a technique for calculating an image feature from the contour line of the head and the region around the shoulders of a person detected from an image, to obtain the orientation of a human body.